Confused! Help?

I recently came across a post where a girl posted a picture of he toilet paper that had an orange tint to it. Most of the comments replied and said it was probably ovulation bleeding. So I concluded it was that for me as well. But I've been having these weird cramps since I've noticed the "spotting" and I've been super gassy. I did have unprotected sex basically all weekend but we're positive he didn't cum inside me..And I just finished my period Thursday of last week.